Screening of high lipid content and productivity of microalgae under photoautotrophic cultivation for biodiesel production

Microalgae are globally accepted source of fatty acids (FA) due to their cell's potential to efficiently accumulate triacylglycerides which contain a significant amount of fatty acids for biodiesel production. This study aimed to screen nine (09) green microalgae strains in the laboratory for their high biomass and lipid productivity. Various microalgae strains were cultured at 30 degrees C, with a light to dark ratio of 16:8 h (10-12 klux of light intensity) and aeration supplementation of 2% CO2 for longer period of time. The fatty acids of all microalgae species which showed growth potential under photoautotrophic cultivation had similar fatty acids found in palm oil. The selected strains of Ankistrodesmus sp. IFRPD 1061 and Chlorella sp. IFRPD 1092 were used due to their high lipid productivity content, were cultivated in 100 L NS III medium in an open raceway pond, aerated with 2% v/v CO2. The biomass concentration and productivity, lipid concentration and productivity of Ankistrodesmus sp. IFRPD 1061 (0.865 g/L, 76.250 mg/L/d, 0.167 g/L, and 14.685 mg/L/d, respectively) were found to be higher than those of Chlorella sp. IFRPD 1092 (0.433 g/L, 31.250 mg/L/d, 0.137 g/L, and 8.528 mg/L/d, respectively). Ankistrodesmus sp. IFRPD 1061 showed potential results of growing microalgae under photoautotrophic cultivation for biodiesel production.